The SaeRS two-component system in Staphylococcus aureus controls the expression of a series of virulence factors, such as hemolysins, proteases, and coagulase. The response regulator, SaeR, belongs to the OmpR family with an N-terminal regulatory domain and a C-terminal DNA binding domain. To improve the production and stability of the recombinant protein SaeR, l-arginine (L-Arg) was added to the purification buffers. L-Arg enhanced the solubility and stability of the recombinant protein SaeR. The thermal denaturation temperature of SaeR in 10 mM L-Arg buffer was significantly increased compared to the buffer without L-Arg. Microscale Thermophoresis (MST) analysis results showed that the SaeR protein could bind to the P1 promoter under both phosphorylated and non-phosphorylated status in buffer containing 10 mM L-Arg. These results illustrate an effective method to purify SaeR and other proteins.

金黄色葡萄球菌中的SaeRS两组分系统控制一系列毒力因子的表达，例如溶血素，蛋白酶和凝固酶。响应调节剂SaeR属于OmpR家族，具有N端调节结构域和C端DNA结合结构域。为了提高重组蛋白SAER，生产和稳定性升将-精氨酸（L-Arg）添加至纯化缓冲液。L-Arg增强了重组蛋白SaeR的溶解度和稳定性。与没有L-Arg的缓冲液相比，在10 mM L-Arg缓冲液中SaeR的热变性温度显着提高。微量热电泳（MST）分析结果表明，在含有10 mM L-Arg的缓冲液中，SaeR蛋白可以在磷酸化和非磷酸化状态下与P1启动子结合。这些结果说明了纯化SaeR和其他蛋白质的有效方法。